A wire feeding device is used to convey a fine wire for a welding machine or a machine used to repair precision objects. In recent years, with the advent and the rapid development of 3D printing machines, not only 3D printing technology is gradually popular but also the related materials or wire feeding devices for 3D printing have become the focus of the research and development or improvement of the relevant industry. The existing wire feeding device is bulky, so it is difficult to be combined with a working machine. In addition, if the stability or accuracy of conveying a wire is not good, it will also have a great impact on welding products and defects.
In order to improve the above-mentioned shortcomings, TW Patent Publication No. 1429575 discloses a “wire feeding roller mechanism”. The wire feeding roller mechanism comprises a wire roller assembly and a drive device above and below a machine base, respectively. A cylinder slide is provided in front of the wire roller assembly. A vacuum wire feeding device is disposed on the cylinder slide. Thereby, the drive device of a toothed pulley assembly drives the roller assembly to convey a wire and the cylinder slide is moved synchronously. When the wire is conveyed smoothly and the cylinder slide is moved back, the roller assembly clamps the wire. By means of vacuum suction, the wire is kept straight and conveyed stably, achieving an accurate and stable effect for conveying the wire.
TW Patent Publication No. M415014 discloses a “portable wire feeding mechanism”. The portable wire feeding mechanism comprises a power unit, a driving roller, a wire feeding roller, a pressing roller, and a pressing lever handle. The pressing lever handle is connected with the pressing roller through a pressing lever and an arm. Two sides of the joint of pressing roller and the wire feeding roller are provided with sleeves as an inlet and an outlet. When the power device drives the driving roller to rotate, the driving roller drives the wire feeding roller so that a welding wire is outputted from a welding wire guide groove disposed above the wire feeding roller and the pressing roller, with a simple structure to achieve the effect of adjusting the speed of conveying the welding wire.
Japanese Patent Publication No. 2003-001421 discloses a “welding wire feeder for a welding machine”. The welding wire feeder comprises a first rotation axle, a second rotation axle, and a third rotation axle. The first rotation axle is wound with a wire. The second rotation axle is provided with a drive wheel. The third rotation axle is provided with a driven wheel. The driven wheel is disposed on a lever member. The lever member is disposed on a mounting frame. A bolt is screwed to the lever member for bringing the driving wheel to get contact with the driven wheel. The wire of the first rotation axle is inserted through a guide hole and a groove of the drive wheel and then out of a nozzle. The drive wheel has a non-slip portion to prevent the slack of the wire.
However, although the above-mentioned wire feeding devices can achieve the effect of preventing the wire from slipping and precisely conveying the wire during the conveyance, they cannot be directly installed to a nozzle. Furthermore, the length of a conveying tube cannot be adjusted according to the demand of working. It is inconvenient for assembly and use. Besides, the wire feeding device doesn't provide a protective gas. Therefore, when the wire is used for metal printing or welding, it is easy to cause the molten metal to be oxidized by the influence of oxygen.
In addition, Taiwan Patent Publication No. 1225435 discloses a “welding wire feeding device”. A metal wire feeding path is formed between a wire accommodating container and a welding torch. The path is provided with a plurality of metal wire feeding units. One of the metal wire feeding units is provided with a drive source to generate a drive force for driving the metal wire feeding units. The drive force is transmitted to the welding wire by a torque limit device. The metal wire no matter in an acceleration or deceleration state can maintain a stable feeding and avoid bending of the metal wire. A gas cylinder is used to spray an inert gas toward the molten body was so as to shield and protect the welding part. However, the above-mentioned wire feeding device cannot be directly installed to a nozzle and cannot adjust the length of a conveying tube according the demand of working. It is still inconvenient for assembly and use.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems.